People who work on Mount Desert Island and the offshore islands and their families enjoyed a mammoth Fourth of July picnic and fireworks display on the shore of Somes Sound.

The hosts, William P. Stewart and his wife, Barbara, threw their waterfront compound open to several thousand of the invited guests for his annual party that amounts to a high point of the year for the trades people, craftspeople, teachers, caretakers, housekeepers, shop clerks and all the other folks who work all year and keep the community operating as a magnet for the yearly influx of summer residents.

Mr. Stewart, chairman and CEO of the WP Stewart Co., a worldwide investment advisory firm, neither seeks nor gets publicity for the huge party, but the couple deserve credit for an imaginative and probably unique example of community philanthropy.

The food alone was spectacular. Caterers served steaks, hamburgers, salads, soft drinks and desserts as a band played and country music star Reba McEntire sang for an hour. Children romped at a carnival, winning prizes by throwing hoops at a horse’s neck, trying their strength at a hammer game, sampling cotton candy and riding a small train that snaked through the estate. One mother said afterward that “the nice thing about it was that it was all free.”

As night began to fall, the boom and glitter of a huge fireworks display began and went on and on before the happy crowd and other observers on boats moored out in the sound.

The Stewarts mail out 2,500 invitations every spring to the working people of Mount Desert Island. This year, about 3,200 people showed up, including children. Not the summer visitors, however. The Stewarts can entertain them at other parties.